Gao Fenghua, Ward Michael P, Wang Yan, Zhang Zhijie, Hu Yi
Anhui Provincial Institute of Parasitic Diseases, Hefei.
Geospat Health. 2018 Nov 12;13(2). doi: 10.4081/gh.2018.730.
Schistosomiasis remains a major public health problem in the South China, particularly in lake and marshland regions. Modelling the spatio-temporal pattern of schistosomiasis guides disease prevention and control programs and is a research area of growing interest. However, few attempts have been made to evaluate the changing (nonlinear) effects of environmental determinants on schistosomiasis. In this context, a hierarchical spatiotemporal model was applied to evaluate how environmental determinants affect the changing trend of schistosomiasis in Anhui Province, China, based on annual parasitological and environmental data for the period 1997-2010. Results showed that - compared to changing effect - environmental factors had a constant (linear) effect on schistosomiasis. The disease was also found to fluctuate over time, which was due to the two latest national schistosomiasis control programs. In addition to statistical benefits of this approach, our analysis implied that climate change might not contribute to variation of schistosomiasis; rather, prevention activities affect schistosomiasis when the disease prevalence remains at a low level. Finally, the analytical method proposed in our study provides a template for modelling the spatio-temporal pattern of a disease whose transmission is largely determined by environmental determinants.
血吸虫病在中国南方，尤其是湖泊和沼泽地区，仍然是一个主要的公共卫生问题。对血吸虫病的时空模式进行建模有助于疾病预防和控制项目，并且是一个日益受到关注的研究领域。然而，很少有人尝试评估环境决定因素对血吸虫病不断变化的（非线性）影响。在此背景下，基于1997 - 2010年期间的年度寄生虫学和环境数据，应用分层时空模型来评估环境决定因素如何影响中国安徽省血吸虫病的变化趋势。结果表明，与变化效应相比，环境因素对血吸虫病具有恒定的（线性）影响。还发现该疾病随时间波动，这是由于最近的两项全国血吸虫病控制项目所致。除了这种方法的统计学益处外，我们的分析表明气候变化可能不会导致血吸虫病的变化；相反，当疾病患病率处于低水平时，预防活动会影响血吸虫病。最后，我们研究中提出的分析方法为对一种其传播很大程度上由环境决定因素所决定的疾病的时空模式进行建模提供了一个模板。
